如果lgx=lga+3lgb﹣5lgc,那么( )
A.x=a+3b﹣c B. C. D.x=a+b3﹣c3
C【解答】解:∵lgx=lga+3lgb﹣5lgc
=lga+lgb3﹣lgc5
=lg,
∴x=,